Telephone system.



' 1131.520 1917. mums-snap.

T. e; MARTIN. I TELEPHONE SYSTEM. APPLICATION FILED "All. 1!. l913i 1 Wanted UNITED STA Es PATENT OFFICE.

'mmo'r G. mnum, or cinema; mnmoxsnssr'nqa '20 Annmar e Emcmm commmz, OF CHICAGO, ILLINOIS, A conromvnon or iLLmoIs.

mmrnonn SYSTEM.

Patenl ed Mar. 20, 1917.

Applicaticzi filed March 17, 1913. Serial No. 754;!01: I

To allwhom it may camera: I i l Be it 'known that I. Tanno'r (ii; MARTIN, a citizen of the United States of iXnieriem-and resident of Cl1ieago, Cook county, Illinois, haveinvente'il.pertain new and useful l nprovements in'Telephone Systems, of winch the-following is a'speeification;

My invention relates to improvements in telephone systeins, and moreparticularly to a system of -'the semi-automatic type-that is. a system inwvhiehboth manual and autor employed in establishing a 11 ii a "call i'na'l' a} called suhsferibers line. Insueh systems, when an operator connects with the through the medium of an automathswiteh, it has heretofore been customary to provide means for transmitting a busy signal back over'the calling: line inease the called line was busy. In'su'ehinstances. li(')\\fe\'el",'tlie. operator would not receive such busy signal' unless .sheoperateil her listening keyso as to eonnecther talking and listening set with the talking circuit. i

An object oi my llIYGIltiUll is to give to'tlie operator ahusy signal the operation of.'

which is not ilepenilent upon any specialaet i of the operator. such as theoperatingbf her listeiiing keyas in former practice.

lit-oressuieeilieally- ITi YJHYQIItIOIL relates to the provisioi'i of meansfor givil g this busy lates tounimprovedarrangement of the in signal by. eausing a perioglieflashing oftlie call ng su )erv sory lamp of the poi-(1 eirruit when theeonneetor switch lands "a busy i I linen".

A: further feature of my invention r'e (livid ual'line equil'nnent, By this feature "the line-switch, whieh is i inliviilua lto a-sub.--

seribefis line; comprises only an aetiiating magnet,- but has no l ne or cut-off. relays; Associated Wltli each line, however. there are separate and (listinet relays one a'line relay anti the other a rutofi' relay. which are sinnlarf to the line aintleut ofi relays of the a well-known manual systems.

matie p1- a} semi autoinatie line. as in the off rel be nsefdfin' the automatic se1ni-' is controlled-by impulses overone side of ealleil line.

telephone T (Fig.

inks-1mbeing! called, are provided with terminate. in multiple jacks J,

v The ob f jeet" of- 'this', arrangement is to'provide m simple" and" economical. manner" in which a: manual line, can be eonverteti into an autoof my invention is a the improved arrangement of the connector switch which is eniploy il to connect with the suhscribefs line. This connector sw-iteh is provided withhut a single line relay which the line only, which lire relay controls both the vertical and rotary inotions of the switeh. These and other obj eets of invinrention will be more readily understood by reference to the accompanying d1 awings; in whieh Figurel represents liagrannnatieally the layout of a telephone system eniln'alyi'ng the prineiplesot-'niyinvention.

Figs. 241ml taken t gether represent-(liagranln'iatieally the apparatus by which a eoni'ieetion nav be established between'a calling telephone l (Fig. 2) and a called In Fig. 1 there is ie 'iresented a manual telephone switehboar l' B L'together witlrtwo groups ;.of telephones A anti AC each of which groups is provided atthe switchboard M with a group of ans .vering 'jaeks J onone V operators position aneli group of multiple Jacks J on other operators positions. At A? there. is" shown a groupof lines whieh, instead of tel-initiating inanswering jacks ion therentral ofiiee;switi-hboard; terininate in autolnatie trunk-sel'eeflng switehes- C. by means of which swit hes idle trunk lines leading to answering j ae'ks J niay be selerteih These subserihers lines Afl' insteail of being provided with the usual multiple multiple calling te'rniiiiais in tl pl'lllillity ofauttuuatir connector switches E, "which switches are'eonnected with the eentrai ofiice s\\it -'lil)oai d by iiieans of .a-n'nk lines which The appara us shown 'in Figs. an cl the apparatus bro'ugln into use when too 9 neetion is inside; between two telephonesof the groupvA 'Whl f r are associated with. the branch otiicel ,The substations T and T7 are 1 ordinary eoininon ha ttery luaniualusuhstationseomprising a receiver 2. transmitter 3.

induction coil swit'cii hook #{riiigr 6 and eondenser f7. The tri' nk selectmg switch Q is of the'fgenera1 type of tinn'k-selectingilw switehi shown and iiescrihetl in British Patent t --'R 1QW* T mes- NQ. 26,301 at 1906- and: BritisliPatn to :Ggltiartixi No. 1419M 11910. As. s'howii I e1 einQQthis switch "tom prise among other eet'ail's a plungep il j shown) attached to me end o'f a gem Jadab I electromagnet 9, thrusts said pluswitch D in such amanner that said 1'0 plunger arm. 8 which, when attracted by an or into some one of a plurality of groups contactspri j'11,-12,13,14,1'5,16','17 and-18, each oups forms the terminal of a hunk; line eading-to-a jack J at the manual tchboard. The plungers of a group of a switches G are controlled by a master Iplungers, when idle, always stand opposite t e terminal of an idlejtrunk' line. The master switch D is of the well-known type fully described in said British Patent No. 1419 of 1910. In addition to the line switch G there i's'allottedvto. the line of the substation T a line relay 19 anda cut-01f relay -20. These line and cut-0H relays aresiniilar to the line and cut ofi relays of a well-known manual telephone system. In fact, when it isdesired to convert "a manual line of this character into a semi-automatic line of the character shown herein, or intoa an automatic line, it is "-onlyne'ces'sary to remove the usual acks and line mp f rqe js ii 11. 9 ace addihsltreekiiig siifitcli'c, which, unlike the usual .trunkdag-switches, has no line or cut-ofl' relays.

" "Allotted to .the trunk line leading to the In this manner the line and cut-off relays "which were used in themanual system may be very; readily used in an automatic or semi-automatic system.

jack J there area line lamp 21 and aplurality of circuit-controlling relays, the o connected together t strands including the condensers 22 and 23.

- eration of whichwill be hereinafterfull y described. v

At 0 there'is shown an operators cord circuit comprisinga fiair of plugs P and P rough the usual cord The usual answering and calling supervisory lamps 24 and. 25 are controlled through the mediumof they-supervisory relays 26, 27 28 angl29 in"a. ,mii nner which will be fully described. At K and K are shown 'the usual vll -iste ingand rin ingkeys. vAt'KQthem is h, J1 akey by means of. which an automaticcalling device may be connectedwith oneside of the 'cord circuit. This calling deyic'e maybejofi-any suitable type and is herein represen simply by a pair of i i-ingsSO which ay be momentarily sepamrated any number-of times desired tocall any digit. At Ether-e is represented a'con-.

hectori'switch whichisof the general typeof connector: switch shown and described in United States Letters Patent No- 815,176,

issued March 13, 1906, to. Keith, Erickson and Erickson. -Thi's '"connector comprisesessentially a-set of Wipers 31,32 and 33 c ar- .rie'd upon a'rotatably and vertically movable shaft"(not shown), the movements of which shaft arecontrolledby, the so-called vertical and rotary magnets 34 and. 35. The

usual side witch compr sing t 37,-. as and s9 is controlled by he wipers 36, the Privat magnet 40 in .a well-known 'nianmar. 7 The ing of the induction coil 43 is adapted to be intermittently connected with a spring of the relay 45 through the medium of a second interrupter 46 which has a'comparatively low period of interruption. At 47 thereis 1 shown a third interrupter which connects magnet 9, contact 52 and the contactl53 to the spring 48 to ground during the periods in w ich the induction coil 43, is disconnected from said spring by the interrupter '46. It is to be understood, of course, that the busy signaling machine and interrupters are represented herein only diagjrammatically, and that itis within. the scope .of my' invention to employ'any suitable and known type of busy signaling machine and interruter.'-

heline switch C and substation T' are in all respects the same as the line switch C and substation '1 shown in Fig. 2. i I In the drawings there is shown a plurality of batteries Bforsupplying the necessary current for the operation of ,the system.

If desired, only one battery need be'used,

or, preferably, one battery in each exchange.

when the apparatus is situated in two or-.

more separate exchanges.

Ha v'ing given a general description ,of the apparatus, it will now be explaine how a. connection is extended from .the substation T to the substation T scriber at the substation T, .upon removing his receiver from the switch hook, closes the circuit of the line relay 19in the usual manner. .The relay 19, upon energizing,

closes .a circuit extending from ground G through the: contact 50, winding -51-of the the battery lead 5-1, thence through the battery. 13 to groundG. The winding 51,-

The subupon energizing, attr'actsthe plunger arm 8 and armature 55. The armature 55'operates to insertthe 'winding'56 in series with the windmg 51, so as to reduce the current consumption of the switch after it h as been.

once operated. The, plunger arm 8, upon being attracted, operates to cause its plunger to force. the springs 11, 12, 13, .14, 15,.

16,17 and 18into contact in pairs. 2 The engagement' of thesprings 11 and 13 with "thesprings 12 and 14-ex tends',the line connect on'to the jack J I and closes; an energizing circuitfor the delay 57. -Thecircu1t for the relay- 20 is closed by 'the' engagement 60 sig;

' .15 and the; winding of springs 15 and l fi and extends iirom the hattery'lead through the rela 20, and the I closure ofthe' contact 5,8 by the energizetionl'of the relay 57 provides a holding cireuit for the switch C, which circuit extends i from ground G through said contact 58, springs '18 and 17, winding 51, contact 59 56' to the battery lead' 54. Thiseireuit malntains the switch C in its operated "position after its original energizing circuit is broken by thedeenergization of the'line relay 19, which is disconnected from The line by the energization of thecut-ofl relay ,when the springs 11} and 15 are forced into contact by the plunger of ,t-hevswitch. The engagement -of the sprifi'g rs 'm'ia mwr 'oii1' \,"closesi an en'er gizing circuit fOF'tlIQ cut-off relayQO, but extends a guarding potential frornground G tothe connector private bank contact '62 'of the calling line in the banks of all connectors which have. access to it. By the 'elosfire'of thecontact 162 of th'eflrelay 57 a circuit is closed through the line signal rclay 64 atcthegj aekl J. This circuit extends from ground G through the rel-ayfifi, contact-fit), relay 64, contact 162 and impedance coil 167 to'the battery B. The relaytiah upon energizing, closes the circuit of the line A a lamp 21.

The rela'ylifi, which is vincluded 1n the clrcmt ust traced, is also. energized and provides another holding ground from.

40 ground G for the'switch C. After the line switch-G has'operatcrhas almve explained, L connect, 11 calling line with an "idle trunk line, the master switch D operates in .ehae hknoirn;memento ad th P gems of the idlelineswitches toa position 1n front of the next idle trunk line. Upon noting the-signal displayed by the ian1p 2 l l l intoktlie jackJ, throws the listening-key 5t) to-hmdge the talking set Sacross the cord O andim uiresthe number of the station de sired. "poll the insertion of the;.plug l i Into the Jack J a circuit is closed extending plug thence to the sleeve and ring-eon- I diletorsof jacltJ and througlrthe relays (39'an l iu= 1nult1ple; t'o ground. The relay 6'9 alf relay The relay'QT of the cord, Mining, closes the contact 71 in the e se atpractically the same time rokefln by the opening of the t eoperator' lnserts t he plug l of the cord on 'ene'rgizi-ilgg opens the circuit of um v l I the lamp 24, but saicl'l-lamp is not iizedover a circuit extending fromground througl said relay, tip of the plug P and 'ack I, contact 162 and impedance coilfii. I Afterasc ertaining the number of the substation-desired, and on finding that it is a station oflhe smi-automatic hranch-ofiice, the operatorinserts the plug P into a 'jack Jfiofan idle trunk lineleading to a connee or switdi E. Upon the engagement of the sleeve cf the plug with' the sleeve of the jack aeircuit is closed extending from ground Gr through the resistamcey'l'Z-l, sleeve ofthe jack and plug and through the super-- visory relay 29 of the cord to the battery The relay 29, upon energizing closes the contact 74; in the circuit of the lamp 25 and bridges the listening key-com tact in the 1 ip side of the cord by the contact 75. The relay 28 is energized ovcracircuit extending irom ground G thrqughthe said relay, tip of the plug P, jack J'Mmd the relay 77 to the battery lead' 78. The relay 77,11pon energizing, closes a circuit through theslow ac! ing relay'79. Therelay 7 upon energizing, closes the circuit of a second slow acting; .relay 80. The operator now operates thev 'key K whereby the rclay'28-is disconnecteil from the tip side of the plug P? and a ct nnection is completed to ground through the calling (le vice' springs 30' with outinterrupting the circuit of the connector line relayfi'l'Q The operator now operates her calling levice for-the successive digits of the number of the substation T", which will be assumed to be 20. Upon the operation of the calling device for the firstdigiti the 'impulse spr ings 30' are'opene'dtwice momentarily, cans ng theconnector line relay77 to V be 'lnon'ie-ntlrily deenergized twice. Since 105 the relay 74' is slow acting, it does not have timeto de nergize during the nunncntary interruption of its circuit by therclay 77, and, tllerefn'e, each timejsaid relay 77 (he energizes a circuit closed from groun'd'tir 1 1'0 through tlu contact 81, contact 82 ,"relay 83, vertical ma Inct 3:4 and side switchwiper38 to the battu'y lead The magnet 34km crates in response tothe 'twoimpulses mg ccivcd'orer this'circuit to raise the wipers; 1 15 of the switxh l1 ton position opposite"tl '1"e second row n' level ot tshank contacts. lhe relay 83, \'lnch is included -1n c1rcuit"ii t series with tlreuuagnct 3+, is a slow act 5" *to closethc (llmllllflf the private magnet 40 dm'ing'the cntire tiinclthe iul mlses are' l-ieingg 'livcrcd the relay 83,deenergizes-and breaks.

second posi :ion. The side switch wiper-'38; I 111 niov-inglgi rom first to second posltiomdli connects 1th battery from the ;vertical ma3g net, 34' and establishes a battery connectio'ni 18p u clay and lcnmins' in- -its energized 'positltm 12o trans'lnittcd, After the last impulsel ist le for the rotary magnet 35. The operator now crates her calling device forfthe second digit 0, whereb the connector linarelay'77. is momentarily eenergized ten times. Each time the relay 77 deenergizes in this instance an impulse is transmitted through the relay 83 and the rotary magnet 35. The.rotarymagnet operates in response tbjthese impulses to rotate thewipers '31, 32 and 33 ten steps onto the contacts of the called line,

after which the relay 83 operates in the same manner as for the previousdigit to cause the private magnet-40 to advance the sideswitch a second step-that is, from second to'third osition+providing the called line isidl e. .he side switch wlper 39, upon'passin'g to I third position, closes anenergizing circuit through .the cutoflt' relay, 8'? of the called I line, said circuit extending 'from grcund G through said side switch wiper, privatewiper 33, bank contact 140 and 'the relay 87? to the battery lead 78. The 'relay- 87,

- upon energizing, disconnects the line relay 88 from the line in -theusual-manner? The side switch wipers 36 and 3Z,' upon passing to third position, complete the line connection through the cord to the called line and t the wiper 36 cuts 0d the line relay 77. As

soon as the side switch wiper 37 engages'its third-position contact a circuit is closed extending from ground G throughythe side switchwiper 39, springs .84 851and 86, 'relay' 8?, side switch wiper 37, jack J ,-plug P and the relay 29 in the cord 0 tothe battery lead 68. The relay 87, upon energizing,- provides a new holding circuit for the relay 79 afterits former .energizin circuit is broken byfthe deenergization 0 the linerelay 77. After calling the lastdig-it the operator at the cord- 0 restores the key K and operates the ringing key K' in the usual manner to rin "l the called subscriber. Upon the response 0% the" called subscriber histelephone is" supplied with talking current through 'the supervisory relays 28 and 29' inthe cordO'Liii the usual manner. The relay '28 now" energizesiorgthe first time. since itw'as disconnected by the calling device key K and by open- "ing the contact 90 breaks the circuit of the lamp 25 to, signify tozthe operator that the called subscriberhas answered,

In the above description it has been as-. sumed'that'the called line. was idle' at the time the connector E attempted to make connection therewith. It said line had been busy no connection could have been made therewith, and the-calling subscriber andthe operator would have beengiven a busy nal in the followingmanner: Whenevei""a.

line is busy, either on account .ofhaving made a ic'all or on account of-havi been called, there is a, guarding ground ential upon its connector private bank contact.

- Assuming. that there is a ground potential.

upon the contact 140 -at ..thetime when the .wiper 33 is brought into engagement therewith, it willybe seen that, slnce the side switch is then in second position, said ground potential is-extended'through said wiper 33, side switch wiper 39, springs 91 and 92 and the relay'45 to the spring 93 of the private magnet 'relay 83. This being the .case, the circuit of the private magnet is not brokenwhen therelay'83 deenergizes after the last digit is called, but said magnet becomes include'd'ili a locking circuit in series with the relay 45. Since the private magnet 40 does not deenergize, the side switch remains locked insecond osition and the connection between the ca ling and the called lines ismaintained open at the sideswitch wipers 36 and 37 Therelay 4-5, upon enerizing, transfers, the holding ground for itself and the private magnet 40 from the guarded private bankcontact of the busy line to the ground G by way of ,the' springs 92, 94 and 196. 'Upon the closure of the contact between the sprin s 48 and 96 by the -re'layf45, the busy signa mg machine L is connected with one side of the cord 0 and the calling line through the side switch wiper 36. By means of the i-nterrupters 46 and '47 the busy signaling inachine'and the ground G? are alternately connected with' I the line. Each time the busy signaling machine is connectedwith the line, busy signaling current is. transmitted to the calling sub station-over a circuit extending from the batter lead 7 8 through the secondary winding 0 the induction coil. 43, condenser 97,

interrupter '46-, springs 48 and 96, side switch wiper 36, jack J, plug P, contact 100 (the key K having been released as'soon'as the last digit was called), thence over the heavy conductors to and through the calling substation and back over the other side of the line, through the various relays. connected thereto to ground, and thence through the battery to the battery .lead- 18.. This busy signaling current is sufficient to notify the calling subscriber that thecalled line is busy,

but unless the operator should operate her listening key K this signalv iyes-her no indication ofthe fact. It wi l be seen, however, that at'the cord circuit the circuits of both the relays 28 and 29 areclosed as was serted into the jack'J". I interrupter 47 (Fig,, 3)- comes into position to ground the tip side of the trunk itshortcircuits the relay 28 at the cord circuit. The relay 28 thereupon deenergizes. and closes the described when the plu%hP' was that in'- en; howeveigthe circuit of the lamp 25. It will thus be Seen that aslong as the connector switch remains locked in this busy position, the lamp 25 will be periodically flashed, which serves as a visual signal to the operator that the called line is busy and-that connection has not been completed therewith. Upon the termination of the conversation inmate the operator is given the usual disconnect signalsby the hanging up ot the receivers at v the calling and called snbstations in the following manner: When the receiver at the calling substation T is re laceduponthe switch hook the circuit the relay 57 is "broken. The relay 57,- upon deenergizi'ng,

breaks the circuit of its cord supervisory re.

1ay26 at the contact 162 "lhe'rela 27 in the cord, however, remains energized t irou h the relays (i5 and 69, and there ore, when t e contact 72 is-closcd-by the deeucrgization of the rclayflfifthe circuit of the answering supervisory lamp 24 is closedhW'hen the rethe circuitof the relay 80. Therelay 80,

eeiver at thecalledlsubstation'T' is hung up the energizing circuit 'of the'relay 28 in the cord circuit is broken, while the relay. 29 re inains energized through the resistance 73 theljack 'andiithrough"the relay 87*atlthn, connector E. The relay 28, upon denergizing, therefore completes the circuit ofthe call-r ing s'upervisory'lamp 25 at the contact'90. Alltthe automatic apparatus'employed in the conncction is released a on the removal 0 the age's-(air fliy th'e' operator? I pon the removal of the answering plug P from the jack J the circuits'of the relays27, (ilia'ndfifi are broken. The relay upon (loi ncrgizing, destroys the'holding circuit oi the switch (I, since the relay 57 has already dein'crgized and disconnected the ground G Upon the interruption ofits holding circuit the magnet 9 denergizes and permits the plunger to be withdrawn from its bank to disconnect the calling line from the jack J T pon the removal of the calling' plug P from the jack J by the operator the circuit of the relay 29 in the cord andtherela 87 in the connector is'ib roken. Upon the en crgization'of the relay 87 in the connector the circuit ofthe relay 79'isbrokn, which made in the line switch and the connector S\Vli]Ch,- it is, of course, understood that these features are equally aswell adapted for'use in connection with a full automatic system-' that is, a system in which a connection-is established wholl by automatic means. Various other modifications will readilysuggest themselves to those skilled in the art. L a What I claim as my invention is 1 1. In a telep hone system, a calling and a coiled subscribers lineymeans including an operators cord c|rcu1t 'f0r establishing a connection between sald'line's, means for giving thecallin subscriber anaudible signal,

a visual signa' for indicating to theoperator that the called line is busy, separate operatmgyi'rcuits for said sigha'ls and ,ari .automatlc progress vely movable switch fortesting. he called line, said signalsoperated al- -ternate ly. A i l 2., In a tele ihone system, a calling and 21 called su'bsci'ibers' line, means including an operators cord circuit for establishing a connection'betveen said lines, means for givin" the c'a'lli'n' subscriber a signal when the lattcrvrelay, upon energizing, in turn breaks upon dei nergizing,completes the c'ircuit'of the release nzmnet 41, said circuit extendinm from gamed" Fi tmtagh'themeds1 0? the line relay, contact'JOI of {the relay 80, magnet 41 and thefcontact 42 to the battery load 78. The n1agnetj 41,"upon energizing,

iu'imediately. lgels'toi-gsthe connector switch to its normal positiomand when the shaft of said switch reachesiits lowest position it" opens u-lemhmct 42, \i'herebythe release magnet 41 isperniitted to dei nergi'ze, Ttwill thus beseen that I-have devised \'cr '-eflicient means for indicating to an op-. cl'atoi the fact that'a called lme is busy.-

\Vhilc I have llustrated thist-ini'ention 1n couuertiou 'th a semi-automatictelephone svstomrit will, of course,; ghe i'inderstoo that m certain:.lu oader aspects my, invention is not limited to sucha system,-but that certu'iu features might be useful in connection witha l-uaniullsystem', Furthermore, in con :nection with the improvements which I have ca ed line is usy,a separate signal for indicating to the operator thatthe called 1i} e is busy, separate operating circuits for, aid

signals, and an automatic progressively movable switch for testing the called line, said signals op eratedralternately'.

' 3. In'a telephone system, a calli-ng'a-nd a 'calle'd' subsci'ibers line, means including an operators 0 0rd circuit for establishing a connection between saidlines, a supervisory "lamp in said cord circuit, means for giving the calling sub: :criber an audible, signal when the called line is busy, means'for operating said stqurvisoiy lam to indicate to the operator thatthe calle line is busy, and separate ope'r-atin circuits for operating said busy signals a zernately.

4. In a 'telephone'system,a-callin and a I called subscribzrs line, means, inclu" ing an operatorfs cord circuit for establishing a connection bet veenfsa-id lines, a supervisory circuit in siiug-cord circuit comprising a lam 1 whereby the operator may su )ervise sal operating said lamp to indicate that the connection, meansfor Iintermi tently.

called line is busy, and'aseparatebusysig- WPMH Y naling clrcuit, said signals operated alters 1 nately. a

" n a telepaonesystem, a called line, an

o erators core-circuit a connector SW1 ch cuit, means for controlling said connector switchi to exten l the connection to said called line, and meals comprising acircuit for grvin said operator a visual slgnal if the" called line is busy, and a separate busy signaling circuit, said signals operate(l"-alternat'elv. 6. In a telep hone operatofscord circu t, an automatic switch system, a calledvline; an

7 adapted to be connected therewith, means called 1i!18'i$ busy, and aseparate -nalin g circuit, said. signals operated nate forcontrolli said switch to extend-a con; nection to sai called line, a circuit insaid cord circuit comprising a lamp, means for if the 7 alterintermittently operating said lamp lay,' n 1eans 'for intermittently shunting said relay when the called line, is busy, and a signal .controlled by said relay.

. 8. In a telephone system; a 'calling' and a called subscribers line, nieans including an operators cord; circuit for establishing a connection between said l1nes, a pa r of relays bridged .acro'ss'. said cord circuit, a

supervisory signal controlled by the conjoint action of Said iillifiiQLfisrQzmg I both-of saidielays, andmeans for intermit tently short-circuitin-g o'nepof saidmelays when the called line-is busy to thereby intermittently operate said signal.

. 9.. In a telephone system, a calling and a called snbscribers line,means for estab lishing a connection between. said lines,

' means including two-separate circuits for giving two distinct busy' signalswhen 'the calledline is busy, "and an" automatic progressively movable switch for testing the called line, said signals operated alternately. 10. In atelephone system, a callingand a called subscriberjs line, means for extendin a connection'from said calling lineto sai called. line, a busy signal machine for sending an interrupted signal to said calling subscriber when an attempt is ,made to establish connection with a busy called line, means for grounding-the line between said interruptions, and a visual busy signal cpntrolled q by said grounding; I '11. In'a telephone system, a calling and a called s'ubscribers line, means including an operators cord circuit and an" automatic switchfor extending a 'connectitm from said callingline to the called line, a busy signaling machine associated w1th sa1d switch for;

'. transmitting a'busy signal back over the line through said cord circuit to.the.calling'line,

an interrupter associated with said busy Signaling machine .for intermittently interruptin'g said busy signaling. current, a second interr'upter.forfgroundiiig the line between the periodsof busy signaling current, and a signal at said cord" circuit operated by. the

grounding of said line to thereby give a.

busy'signahto said operator.

12. In'a'telephone system, it called line, a

'cord circuit, all-automatic switch-.controllable through said cord circuit for establishing a. connection with said line, a relay in fa callin and a said cord adapted L be 'energizcd'when connection is established between said cord circhit and said switch, means for short-circuitiIig said relaywhen an attempt is made to establisha connection with a busy line to thereby deenergize said relay, and a signal contro l relay. 4 c e 13. In a telephone s stem, a calling and a called line, means including a cord circuit, an automatic switch adapted to be connected thereto for extendin a connection from the calling to the called his, a pair of relays in said cord-*circuit, means for energizing said relays when said cord .circuit' is connected j with ,saidautomatic switch, means for intermittently short-circuiting one of said rela s when an attempt is made to connect with a busy called line, whereby said relay is denergized, and a sggnal displayed by thedenergization of said relay. n 14. In a telephone system, a calling and a called. subscribers line, means including a cord circuit, an automatic switch adapted to be connected thereto for extending a 'c0nnec'- tion from the calling to the. called line',"a busy signaling machine for transmitting'signalin'g' current over one side. of said cord circuit back to the callin line, an interrupter for intermittently interrupting said busy'signalipg current, a second interrupter for grounding the same" side of the cord between the impulses of signaling current, a relay in said cord circuit adapted to be en-. ergizedrwhen connection is made between the cord and'said switch, to be-de'energized when the side of the cord circuit is grounded through'said-second interrupter, and asignal controlled by the deenergization. of said relay.

. 15. In a telephone system, subscribers" lines divided into groups, means including an operators cm'd circuit and a connector switch tor establishing-a connection between two of said lines, said connector switch having one motion to select groups and a second "motion to find thecalled line in the selected group, neans comprising a circuit forgiving the operatora visual signal if the called line is busy, and a separatebusy signalingcircult, said signals operated alternately.

lines dividedinto groups, means including switc two of for estahlishijn a connection between g-one motion toselect groups and a second an operator; cord circuit and az'connector ed by the, deenergization of said said relay adapted 16. In a telephone system, subscribers said l-ines,, sai connector switch havmotion tdfindthe called iline' in the selected smupw 'el iti dud sg a mp; n n inately.- I

In a telephone system, subscribers linesjdivided into grol'ipg ineans including lines divided' into groups, means inclndin g an operators cordcircuit and a connector switch for establishing a connectlon between two ofsaid lines, saidconn ector switch hav- 5 lug-one motion'to select roups and a second motion to find the calls line in the selected group,.an operators talking set associated with said cord c rcuit, a switclrfor connectmg and disconnecting sa d set from said cord circuit;and-means comprising a circuit operatin irrespective of the position of said an operators ucord circuit and a connector switchforestablishing a connectionbetween two-of said-lines, sa d connector switch having one Il'lOtlOIL to select groups and'asecond motion to find the called line'inthe selected group, and means forgiving two distinct busy signals when the; connector attem ts to busy, said signals operated alternately.

193111 a telephone system, subscribers. lines divided into groups,'m'eans including an op'erators' cord circuit and a connector switch for establishing a connection between I two "ofsaid lines, said connector switch haivingfone'motion to'select groups and a secondLIn'otion,toafindathe called line in 'the' selected "group, a busy""signaling machine as r .y r ting a" busy signalbackoverthe line through said cord circuit to the calling line,-an interrupter associated with said bnsy'slgnaling machine forintermittently inte'rrnijting sa1d" busy "signaling current, a second interrupter qfor groundingthe'line between the periods of busy signaling current, and a si'gnalac s'ti-idco'rd circuit oneratedby the rounding of said line to thereby give a ,nsy'sign'al to said operator. y a telephone system, subscribers lines divided into groups, means including" ano'perators cord circuitand a connector switch for' establishing a connection between I two of said lines, said connector switch hava ingf onemctfion toselect'groups and a second- "motion to find'the called line in the lselected'group; a relay in said cord adapted to be energized: whenfconnection is establish'edbetween said cord circuit and said switch, Ineanstfor short-clrcnltingsald relay when an attemptis made to establish a 'coni nectionwith a busy li'netothereby denergize said relay 'and a-signal controlled by the deiinergization of-said relay.

' 21L=In" a "telephone sy'htem, subscribers linesdivided into groups, means including an operators cord, circuit and a connector switch for-establishing a connection between two of saidlines, saidconnector switch havmake conne 2tionfwith a called line which is v current, a relay 1n sa'dcord circuit, adap "associatedgwith said connectonfjor transmitin%'[one ihotiontojhe "s aiidu 860- I on motion 'to find the can me" "the," selected group, a pair of relays. inxmiid cor" circuit, means for energizing'saidrelcys when said cord circuit is connected with said 7 automatic, switcl 1, means for fintermit tently short-circuitir g onejoi said: relays whenan attempt is made to'connect withfnbusy called line, whereby 5's, rela" 18"(1 energized, and a sig maldifiifl s deener ization of saidrela'y,

22. I n a telephona system;

lines divided into gr cups, ni'ens mcljud-ing' an operators cord circuit and afconnector' switch forestablishing a connection between two of said lines; said connector' switch hav 'ing one motion to sels ct groups and a second motion to find the cal led line "in the selected group, .a busy signaling machine] for time; mitting signaling current over} one side of said cord circuit back to they-calling line; an interrupter for in termittently interrupting said busy signal in g c'urrent, a second i interrupter for groundlng-the same sidebf the cordJbetween the impulses of signalin' trolled by the dener gization of said-relay. I

23. In a telephone system, calling and called subscribers lines, means includi'n an automatic switchhaw' i ng two sep'arat'es'e ect-. -1ng motions for establishing aconn'ec'tion between said line'sQan d a relay'in said switch controlled by ground impulses over one side of the line only..for controllingthetwo 'motions-of said switch, I r

24. In a telephone system an automatic switch having vertical and rota'ry "motions, and a single line rela y fonsuccessively' controlling'both motion i, one terminal of the' relay being connected to one side of the line, and the other terminal being connected-to battery. 5 e

25. In a telephone system an automaticswitch, atrnnk line extendingto said switch; a relay in jsaid-s'witcl', means for ene'r izing said relay over one slide of said trun 'fline and ground, and means for intermittently I breaking the circuit ofsaid relay; said switch having moticn in twointersecting. planes, both controlled by "said relay; i

'26. In a telephone system, subscribers?) lines divided into "g1 cups; means including an operators cord c rcuit and a connector switch for establishing a connection between two of sa d llnes, salci connectorswitch litivig'motion in one pla tie to select groups and r l a ing motion in onepliineto select groupsand I uid switch'gand' meansfongiving tlie'op .erator avisual signal if the called line '1s 'motion in aplane at ri' ht-angles thereto to find'th'e called line in t e selected group, a relay. controlled-by ground impulses over one side of a line for'controlling two mo tions of said switch, a lamp'in said cord circuit,z and means, for intermittently operating said 'lam'p if the connector attempts to make connectionfiwith a called line which is bllS..

Y 2% In a telephone system, subscribers lines divided into groups, means including an' o'perators cord circuit and a connector switch for establishing aconnection between two of said lines, said connector switch having motion in one plane to select groupsand motion in apla'ne at rightanglesthereto tofind the called line in the selected group, a relay controlled by ground impulses over one side of a line for controlling two motions of said switch, a superviso'ry signal in said cord-.circuit, means for. (lisplayingsaid'signal when a. called sub:

I scriber: responds after connection -has been established with .an idle called line, and means for displaying said signal if the coni 85 nector attempts to make connection with a called line which'is busy.

29. In a telephone system, subscribersb lines divided-into groups, means including an o erators cord circuit and a connector 40 switc for establishing a connection between two of said lines, saidconnector switch-hav-' s 0 0 i consp ne'to ct g o p an motion in aplane at right-angles thereto to find thecalled line in the selected group, a 4i relay controlled byc-ground impulses; over one side of a line for controlling two motionsof sai'dswitch, a supervisory signalin-said c' rd circuit, means for displaying said Slg-- 'nal when acalled subscriber responds after 5. connection, has been established with-anidle.

called line, and means for intermittently dis playing said signal if the connector. attempts to make connection with a called line wluchisbusy.. 5 v 30, In -a telephone system, subscribers lin' r divi ed n o g ps, a e ns including an. operators cord circuit and a connector switch forestablishinga connection between; two of saidlines, said connectors-witch havmotion in a plane at -right-angles thereto to find the-called line in. the selected group, a relay controlled. by ground impulses over one side of a line-'for-controlling two mosai'd cord circuit, and means independent of:

operating irrespective of the position of an operators cord circuit and a connector line through said c'ord circuitto thecalling line; an interrupter associatedv with vsaid (lines-dividedinto groups, means including an operators'c'ord, circuit and a connector 'tions' of said 'switch,'an' operators set normally disconnected from said cord circuit, a key switch for connecting said set with said set for iving a signal to the operator if the called inc 1s busy.

31. In a t lephone; system, subscribers line's divided into groups, means includingan o erators cord circuit'and a connector switc for establishing a. connection between two of said lines, said connector switch hav mg motion in oneplane to select groups and motion in a plane at right-angles, thereto to find the called line in the selected group, a relay controlled by ground impulses over one .side of a line for controlling two motions of said switch, an opera-tors talking set associated with said cord circuit, a switch for connecting and disconnecting said 'set from said cord circuit, and means said-switch for indicating to the operator that the called line is busy. 32. In a telephone system, subscribers lines divi'ded'into-groiips, means including an operators cord circuit anda connector switch for establishing a connection between two of said lines, said connector switch having motion in oneplane to select groups and motion in a plane at right-angles thereto to find the called'line in the selected group, a relay controlled by g'roundimpulses over one side of a line for controlling two motions of said switch, and means for giving two disktinct' busy signals when theconnector at tempts to make connection with a called line which is busy.- 1- f 33. .In a telephone system, subscribers 7 lines divided into groups, means including switch for establishing a connection between 1 two of said lines, slid'connector switch hav-- ing motion in one plane to select groups and motion in a plane at righte'angles thereto to A find the called line in the selected, group,- a relay controlled by ground impulses 1 over one side of a line for controlling two mo; tions ,of' s'aid switch, a busy' signaling machine associated. with said connector forl transmitting a busy si 111' back over the busy signaling-machine for intermittently f interrupting said busy signaling current, rasecond interrupter for grounding the line between the periods of busysign'alin'g current, and a signal at said cord circuit. openated by-the grounding of. said line to thereby give a busy signal to said operator.

34.-In a telephone system, subscribers switch for establishing a connection between atwo of said lines, said connector switch hav motion in a plane at right-angles thereto to find the called line in the selected group, a relay controlled by ground impulses over a one side of a. line for controlling two motions it of said switch, a relay in said cord adapted to be energized when connection 1s established between said cord circuit and saidswitch, means for short-circuiting said i relay, whenan attemptis made to establish a connection with a busy line to thereby deenergize said relay, and a signal controlled by the deenergization ofsaid relay. 35. In a telephone system, subscribers 16 lines divided into groups, means including an operators cord circuit and a connector switch for establishing a connection between two of. said lines, said connector switch having motion in one plane to select groups and busy called line, whereby said relay is deenergized, and a signal displayed by the de- "energization of said relay.

- 36. In a telephone system, subscribers lines dividedinto groups, means including i 85 an operators cord circuit and a connector switch for establishinga connection between two of said lines, said connector switcli' having motion in one plane to select groups and motion in a plane at right-angles there- 49 to to find the called line in the selected group, a relay controlled by ground -impulses over one side of a line for controlling two motions of said switch, a busy signaling machine for transmitting signaling ourrent over one sideof said'cord circuit back to the calling line, an interrupter for intermittently interrupting said busy signaling ,current, a second interrupter for grounding 1 the same side of the cord. between the im- 5. pulses of signaling current, a relay in said [cord circuit adapted to be energized when connection is made between the cord and said connector. said relay adapted to be deenergized when the side of the cord circuit and a signallcontrollcd by the dei ncrgization of saidrelay.

37. In a telephone system a calling and a called line, means including an operators cord circuit forestablishing connection between said lines, said means includingalso an automatic progressively movable switch between the cord circuit and the called line, means for giving the calling subscriber an -ing motion in one plane to select groups and grounded through said second interrupter.

audible signal, a visual signal for indicating to the operator that tin called line isbus'y, i and separate operating circuits for operatingsaid signals alternately.

38. In a telephone sy: tern, a calling and a called line, means incl iding an operators cord circuit for establishing connection between said lines, said means including also anautomatic progressi ely movable switch between the cord circuit and the called line, means for giving the :alling subscriber a signalwhen the called iine is busy, another signal jor indicating to ",he operator that the called line is busy, and separate operating circuits for operating said signals alternately. i I i i 30 '39. In a telephone system, a callin and a. called subscribers line, means inclu ing an operators cord circuit ft r establishing a connection between said lines, a supervisory lamp in said cord circuit, means for giving the calling subscriber an audible signal when the called line is busy, means for operating said supervisory lamp to indicate to the operator that the called line is busy, said signal. and lamp operated alternately over separate ciibuits, a1 1d an automatic pro gressively movable switch for testing the called line. a

40. Ina telephone s3 stem, a talkin'g-circuit for connecting a calling and a called line, means for testingthe called line, and

means responsive thereto for operating two signals alternately over the talking circuit.

41. Ina telephonesystem, a talking circuit for connecting a (ailing and a called line, means for testing the called line, and means responsive thereto for operatin two signals alternately over the talking circuit, one signal on the calling,' line andone in the central ofiice.

42. In a telephone sy stem, a calling line, a called line, a link for connecting the two lines in a. talking circuit, a signal individual to the calling line, and one individual to the link, a busy test circui'; for the called line, and means controlled t'iereover for operatingthe two signals alternately.

43. In a telephone system, a calling line, i a called line. a link for connecting the two lines in a talking circui1 :a signal individual 115 to the calling line, and one individual to the link, a busy test circui; for the called line and means controlled tierover for operatline circuit and the other over the local circuit, both over a section of the talking c1rcuit.

4,5. In a telephone system, a calling line, a called line, a link for connecting the two lines in a talking circuit, a signal individual to the calling line, and one individual to the link, a busy test circuit for the called line and means controlled'thereover for operating the two signals, said means including a relay and a circuit for directly operating one of the signals, said circuit under the control of the relay.

46. In a telephone system, a calling line, a called line, a link for connecting the two lines in a talking circuiha signal individual to the calling line, and one individual to the -link, a busy test circuit for the called line and means controlled thereover for o erating the two signals, said means inclu ing a relay and a circuit under the control of said relay for directly operating one of the sig- {1315, and means for short-clrcuiting said re- 47. In a telephone system, a calling line, :1 called line, a link for connecting the two lines in a talking circuit, a signal individual to the calling line, and one individual to the linkya busy test circuit'for-the called line,

and means controlled thereover for operating' the two signals, 'one over the line circuit and the other over the. local circuit, said means including a relay and a circuit under the control of said relay fordirectly operating one of the signals. 39. In a telephone system, a calling line, a called line, a link for connectin "the two lines in'a talking circuit, a signal lndividual to the calling line, and one individual to the link, a busy test circuit for determiningif' the called line is busy, a progressively movable switch for controlling said circuit, means for operating the two signals alternately, and'other means controlled over the test circuit for controlling such operation.

50. In a telephone system, a calling line, a called line a link for connecting the two lines in a tallri to the calling. me, and one individual to the link, a bus test circuit for determining if the called ine is busy,- a progressively movable switch for controlling said circuit,

circuit, a signal individual means for operating the two signals alternately, one over th line circuit and one over the local circuit, and means controlled over the test circuit for controlling such operation.

51(In a telephone system, a calling line, a called line, a link for connecting the two lines in a talking circuit, a signal individual I to the calling line, and one individual to the link, abusy test circuit for determinlng if I the called line is busy, a progressively movable switch for controlling said circuit means for operating the two signals alternately, one over the ine circuit and one over the local circuit, both over a section of the talking circuit, and other means controlled over the test circuit for controlling said operation.

- 52. In a telephone system, a calling line, 7

a called line, a link for connecting the two lines in a talking circuit, a signal individual to the calling line, and one individual to the link, a busy test circuit for determining if the called -line is busy, a progressively movable switch for controlling "said circuit and means controlled over said test circuit for operating the two signals, said means including a relay and a circuit under the control of said relay for'directly operating one of the signals.

53. In a telephone system, a calling line, a called line, a link for connecting the two lines in a talking circuit, asignal individual to the calling line, and one individual to the link, a busy test circuit for determining if the called line is busy, a progressively movable switch forcontrollin said circuit and means controlled over said test circuit for operating the two signals, said means including a relay and a circuit under the control of said relay for directly operating one of the signals, and means for short-circuiting said relay;

' 54.-In a telephone system, a calling line, a calledline. a link for connecting the two lines in a talking circuit, a signal individual to the calling line, and one individual to the link, a busy test circuit for determining if the called line is busy, a progressively mov'- able switch for controlling said circuit and means controlled over said test circuit for operating the two signals, one over the line circuit and the otherover the local circuit,

said means including a relay and a circuit under the control of said relay for directly operating one of the signals.

55.In a telephone system, a calling line,

a called line, a link for connecting the two lines in a talking circuit, a signal individml to the calling line, and one individual to the link, a busy test circuit for determining ifthe called line is busy, a progressively movable switch for controlling said circuit and means controlled over said test circl lit for opefating the two signalstono' Sighedty me at Chico; CoOk cOImty, over the line circuit and the other over the Illinois, this 8th hfi ch r G 191 local, both over a section of the talking I TIN. circuit, said means includin a relay and i1 Witn; l5 circuit under the control 0 said relay for Anmm: J. RAY,

directly operating one of the-signals. Enwmb D. Emu, 

